Draining radiators on system with Combi Boiler

[seamyth89]

Hi
I want to drain down the rads on my system after flushing. I have a Celtic Plus combi-boiler. Do I just switch off and isolate the boiler then drain the system or do I also turn off the mains stop-cock? What do I turn off on the boiler - see manual
http://www.aroundtownflats.com/manu...ux/CHAFFOTEAUX CELTIC PLUS GCNo.47-980-07.pdf
Help please

 

[bengasman]

Safest thing to do is to make it absolutely sure that nobody can mistakenly turn the boiler on. If it comes from a fused spur, remove the fuse. If it is plug and socket, remove the plug.

 

[seamyth89]

Thanks but just to clarify my question - I need to know where are the flow and return water valves which will isolate the boiler from the radiators?

 

[bengasman]

1. Best not to touch isolation valves as they more often than not will leak afterwards.
2. Why on earth would you want to fiddle with those in the first place?
3. If you must, the boiler installation manual will show you exactly where they are.

 

[seamyth89]

The manual is not clear enough for me. Can someone else help please?

 

[linkyplumb]

As already stated all you need do is isolate boiler electrically, by any of the ways that bengasman has stated.

Why do you want to isolate the boiler anyway?
Touch those valves and they will leak, causing pressure loss, and then you will have to keep topping the boiler up.

Graham

 

[bengasman]

If you can't work out from the manual where the valves are, you really should leave the job to a pro, as you are likely to do more harm than good when you lack the necessary skills/understanding.

 

[seamyth89]

Thanks for your explanation. Does that mean that the radiators will not refill if the boiler is still connected to them and the water mains is still turned on? So to refill them do I open the screw on the flexible pipe which I use to pressurise the system?

 

[foxhole]

Thats correct, in use the boiler and rads are isolated from mains supply until you recharge it via the filling loop [flexi pipe you refer too].
The mains to the boiler is only turned off to work on taps supplied by the mains or boiler.

 

[seamyth89]

Thanks for your help foxhole